Nav: Home

Neanderthals of Western Mediterranean did not become extinct because of changes in climate

July 20, 2020

Homo Neanderthaliensis did not become extinct because of changes in climate. At least, this did not happen to the several Neanderthals groups that lived in the western Mediterranean 42,000 years ago. A research group of the University of Bologna came to this conclusion after a detailed paleoclimatic reconstruction of the last ice age through the analysis of stalagmites sampled from some caves in Apulia, Italy.

The researchers focused on the Murge karst plateau in Apulia, where Neanderthals and Homo Sapiens coexisted for at least 3,000 years, from approximately 45,000 to 42,000 years ago. This study was published in Nature Ecology & Evolution. Data extracted from the stalagmites showed that climate changes that happened during that time span were not particularly significant. "Our study shows that this area of Apulia appears as a 'climate niche' during the transition from Neanderthals to Homo Sapiens" explains Andrea Columbu, researcher and first author of this study. "It doesn't seem possible that significant climate changes happened during that period, at least not impactful enough to cause the extinction of Neanderthals in Apulia and, by the same token, in similar areas of the Mediterranean".

THE CLIMATE CHANGE HYPOTHESIS

The hypothesis that a changing climate was a factor in Neanderthals extinction (that happened, in Europe, nearly 42,000 years ago) found considerable support among the scientific community. According to this theory, during the last ice age, sharp and rapid changes in climate were a decisive factor in Neanderthals' extinction because of the increasingly cold and dry weather.

We can find confirmation of these sharp changes in the analysis of ice cores from Greenland and from other paleoclimatic archives of continental Europe. However, when it comes to some Mediterranean areas where Neanderthals had lived since 100,000 years ago, the data tell a different story. The Western Mediterranean is rich in prehistorical findings and, until now, no one ever carried out a paleoclimatic reconstruction of these Neanderthals-occupied areas.

THE IMPORTANCE OF STALAGMITES

Where to find answers about the climate past of the Western Mediterranean? The research group of the University of Bologna turned to the Murge plateau in Apulia. "Apulia is key to our understanding of anthropological movements: we know that both Neanderthals and Homo Sapiens lived there approximately 45,000 years ago", says Andrea Columbu. "Very few other areas in the world saw both species co-existing in a relatively small space. This makes the Murge plateau the perfect place to study the climate and the bio-cultural grounds of the transition from Neanderthal to Sapiens".

How is it possible to provide a climate reconstruction of such a remote period? Stalagmites have the answer. These rock formations rise from the floor of karst caves thanks to ceiling water drippings. "Stalagmites are excellent paleoclimatic and paleoenvironmental archives", explains Jo De Waele, research coordinator and professor at the University of Bologna. "Since stalagmites form through rainwater dripping, they provide unquestionable evidence of the presence or absence of rain. Moreover, they are made of calcite, which contains carbon and oxygen isotopes. The latter provide precise information about how the soil was and how much it rained during the formation period of stalagmites. We can then cross these pieces of information with radiometric dating, that provide an extremely precise reconstruction of the phases of stalagmites' formation".

A (RELATIVELY) STABLE CLIMATE

The pace at which stalagmites formed is the first significant result of this study. Researchers found out that Apulian stalagmites showed a consistent pace of dripping in the last and previous ice ages. This means that no abrupt change in climate happened during the millennia under investigation. A draught would have been visible in the stalagmites.

Among all the stalagmites that were analysed, one was particularly relevant. Researchers sampled this 50-cm long stalagmite in the Pozzo Cucù cave, in the Castellana Grotte area (Bari) and they carried out 27 high-precision datings and 2,700 analyses of carbon and oxygen stable isotopes. According to dating, this stalagmite formed between 106,000 and 27,000 years ago. This stalagmite represents the longest timeline of the last ice age in the western Mediterranean and in Europe. Moreover, this stalagmite did not show any trace of abrupt changes in climate that might have caused Neanderthals' extinction.

"The analyses we carried out show little variation in rainfall between 50,000 and 27,000 years ago, the extent of this variation is not enough to cause alterations in the flora inhabiting the environment above the cave", says Jo De Waele. "Carbon isotopes show that the bio-productivity of the soil remained all in all consistent during this period that includes the 3,000 years-long coexistence between Sapiens and Neanderthals. This means that significant changes in flora and thus in climate did not happen".

THE TECHNOLOGY HYPOTHESIS

The results seem to show that the dramatic changes in the climate of the last ice age had a different impact on the Mediterranean area than in continental Europe and Greenland. This may rule out the hypothesis that climate changes are responsible for Neanderthals dying out.

How do we explain their extinction after a few millennia of coexistence with Homo Sapiens? Stefano Benazzi, a palaeontologist at the University of Bologna and one of the authors of the paper, provides an answer to this question. "The results we obtained corroborate the hypothesis, put forward by many scholars, that the extinction of Neanderthals had to do with technology", says Benazzi. "According to this hypothesis, the Homo Sapiens hunted using a technology that was far more advanced than Neanderthals', and this represented a primary reason to Sapiens' supremacy over Neanderthals, that eventually became extinct after 3,000 years of co-existence".

THE AUTHORS OF THE STUDY

The study was published in Nature Ecology & Evolution with the title "Speleothem record attests to stable environmental conditions during Neanderthal- modern human turnover in southern Italy". Representing the University of Bologna, we have Andrea Columbu, Veronica Chiarini and Jo De Waele from the Department of Biological, Geological and Environmental Sciences, and Stefano Benazzi from the Department of Cultural Heritage.

Other scholars also participated in the study: from the University of Innsbruck (Austria) where the isotopic analyses were carried out, from Melbourne University (Australia) and Xi'an Jiaotong University (China), that carried out the radiometric dating.

Grotte di Castellana, the Apulian Speleology Association and, for the major part, local speleology groups provided funding for this study.
-end-


Università di Bologna

Related Ice Age Articles:

Ice discharge in the North Pacific set off series of climate events during last ice age
Repeated catastrophic ice discharges from western North America into the North Pacific contributed to, and perhaps triggered, hemispheric-scale changes in the Earth's climate during the last ice age.
Ice Age manatees may have called Texas home
Manatees don't live year-round in Texas, but these gentle sea cows are known to occasionally visit, swimming in for a 'summer vacation' and returning to warmer waters for the winter.
Sea ice triggered the Little Ice Age, finds a new study
A new study finds a trigger for the Little Ice Age that cooled Europe from the 1300s through mid-1800s, and supports surprising model results suggesting that under the right conditions sudden climate changes can occur spontaneously, without external forcing.
How cold was the ice age? Researchers now know
A University of Arizona-led team has nailed down the temperature of the last ice age -- the Last Glacial Maximum of 20,000 years ago - to about 46 degrees Fahrenheit.
What causes an ice age to end?
Research by an international team helps to resolve some of the mystery of why ice ages end by establishing when they end.
New study results consistent with dog domestication during ice age
Analysis of Paleolithic-era teeth from a 28,500-year-old fossil site in the Czech Republic provides supporting evidence for two groups of canids -- one dog-like and the other wolf-like - with differing diets, which is consistent with the early domestication of dogs.
Did an extraterrestrial impact trigger the extinction of ice-age animals?
Based on research at White Pond near Elgin, South Carolina, University of South Carolina archaeologist Christopher Moore and 16 colleagues present new evidence of a controversial theory that suggests an extraterrestrial body crashing to Earth almost 13,000 years ago caused the extinction of many large animals and a probable population decline in early humans.
Dust in ice cores leads to new knowledge on the advancement of the ice before the ice age
Working with the ice core ReCap, drilled close to the coast in East Greenland, postdoc Marius Simonsen wondered why the dust particles from the interglacial period -- the warmer period of time between the ice ages -- were several times bigger than the dust particles from the ice age.
Ice-sheet variability during the last ice age from the perspective of marine sediment
By using marine sediment cores from Northwestern Australia, a Japanese team led by National Institute of Polar Research (NIPR) and the University of Tokyo revealed that the global ice sheet during the last ice age had changed in shorter time scale than previously thought.
What triggered the 100,000-year Ice Age cycle?
A slowing of ocean circulation in the waters surrounding Antarctica drastically altered the strength and more than doubled the length of global ice ages following the mid-Pleistocene transition, a new study finds.
More Ice Age News and Ice Age Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Listen Again: The Power Of Spaces
How do spaces shape the human experience? In what ways do our rooms, homes, and buildings give us meaning and purpose? This hour, TED speakers explore the power of the spaces we make and inhabit. Guests include architect Michael Murphy, musician David Byrne, artist Es Devlin, and architect Siamak Hariri.
Now Playing: Science for the People

#576 Science Communication in Creative Places
When you think of science communication, you might think of TED talks or museum talks or video talks, or... people giving lectures. It's a lot of people talking. But there's more to sci comm than that. This week host Bethany Brookshire talks to three people who have looked at science communication in places you might not expect it. We'll speak with Mauna Dasari, a graduate student at Notre Dame, about making mammals into a March Madness match. We'll talk with Sarah Garner, director of the Pathologists Assistant Program at Tulane University School of Medicine, who takes pathology instruction out of...
Now Playing: Radiolab

What If?
There's plenty of speculation about what Donald Trump might do in the wake of the election. Would he dispute the results if he loses? Would he simply refuse to leave office, or even try to use the military to maintain control? Last summer, Rosa Brooks got together a team of experts and political operatives from both sides of the aisle to ask a slightly different question. Rather than arguing about whether he'd do those things, they dug into what exactly would happen if he did. Part war game part choose your own adventure, Rosa's Transition Integrity Project doesn't give us any predictions, and it isn't a referendum on Trump. Instead, it's a deeply illuminating stress test on our laws, our institutions, and on the commitment to democracy written into the constitution. This episode was reported by Bethel Habte, with help from Tracie Hunte, and produced by Bethel Habte. Jeremy Bloom provided original music. Support Radiolab by becoming a member today at Radiolab.org/donate.     You can read The Transition Integrity Project's report here.